Group Operations for Stresses and Stiffness

This chapter explains group operations for stresses and stiffness.

This page discusses:

Group Operation for Stresses

For a standard shape optimization definition, the maximum stress over all load cases is selected within the design nodes as follows:

DRESP
 ID_NAME        = DRESP_MAX_MISES
 DEF_TYPE       = SYSTEM
 TYPE           = SIG_MISES
 UPDATE         = EVER
 ND_GROUP       = DESIGN_NODES
 GROUP_OPER     = MAX
END_

Group Operations for Stiffness

For the standard topology optimization task the stiffness/compliance is defined as the sum of the strain energy for all elements in the model. If more than one load case is defined, the overall stiffness is then the sum of the stiffness of the referenced load cases. This can be defined as:

DRESP
 ID_NAME        = DRESP_SUM_ENERGY
 DEF_TYPE       = SYSTEM
 TYPE           = STRAIN_ENERGY
 UPDATE         = EVER
 EL_GROUP       = ALL_ELEMENTS
 GROUP_OPER     = SUM
END_